never having happened before.是什么时态,用到什么语法现象

never having done还是having never done Love means never having to say you'r are sorry Love means never having to say you're sorry. love means never having to say you are sorry? love means never having to say you're sorry love means never having to say you're sorry I have having been never changed to Your feeling Love means never having to say you're sorry. Love.means.never.having.to.say.you.are. Love means never having to say you're sorry. never having happened before.是什么时态,用到什么语法现象 Having been back to original point.Never turning up! love means never having to say you are sorry中的“ have”为什么要变having? having having having 12 _____him before ,I didn't recognize him .A Not seeing B Having not seen C Never having seen D Having never seen是否应把never 放在haveing seen 前面 _____ hard before, Tom is afraid of failing in the exam. A. Having been worked B. Not to have worked C. Having never worked D. Never have worked为什么选C而不可以用Never having worked